Level of bronchial asthma control and direct medical care
costs among adult asthma club members: longitudinal cost
of illness study
SPMC J Health Care Serv. 2015;1(1):25-30.
1Department of Family and Community Medicine, Southern Philippines
Medical Center, JP Laurel Ave, Davao City, Philippines
Correspondence Marie Applelyn Mañalac Fabian, email@example.com
Received 21 May 2015
Accepted 11 June 2015
Cite as Fabian MAM, Concha MEA. Level of bronchial asthma control and direct medical
care costs among adult asthma club members: longitudinal cost of illness study. SPMC J Health
Care Serv. 2015;1(1):25-30.
The worldwide incidence of bronchial asthma (BA) has been increasing in recent years.1
BA accounts for 180,000 preventable deaths per year, becoming the second major cause of adult death and disability worldwide
in 2004, according to the Asia Asthma Development Board.2
An estimate of 10.7 million Filipinos have BA.3
There is an increasing trend in the costs of asthma care.4 5
The average cost per hospital admission related to asthma was USD 6,600 in 2010,
compared to only USD 5,200 in 2000.6
The increasing efforts in controlling asthma complications and the rising range of environmental factors
that affect asthma symptoms can possibly explain this trend. Financial burden in asthma among different Western countries range from USD 300 to
USD 1,300 per patient each year.7
In one study in Canada on the cost of asthma care among children, the societal total costs of the disease were
comprised of hospital admission expenses (43%), medication expenses (31%),
and parent productivity losses (12%).8
In an Asian study done in diverse urban regions in China, Hong Kong, Korea, Malaysia, Philippines, Singapore, Taiwan, and Vietnam, the mean total
direct annual cost for asthma per patient was USD 320. Drug costs comprised about 9% (Hong Kong) to 75% (Philippines) of the total per-patient direct
costs. Filipinos with asthma spent 573% of the nation's mean per capita health care spending on asthma medical care.9
The goal of periodic assessment and monitoring of patients with BA is to determine whether the goals of therapy are achieved and the asthma is
controlled. If asthma is uncontrolled, there is significant asthma burden, decreased quality of life, and increased health care
utilization.10 11 12
We did this study in order to quantify the direct medical care costs incurred by adult patients with BA in relation to the level of asthma
control. We also wanted to determine the sources of funds for medical care and how each of the sources contributes to the total direct medical care costs.
Study design and setting
In 2014, we did a 2-month longitudinal cost of illness study among members of the Davao Asthma Club (DAC) in Southern Philippines Medical Center (SPMC),
a 1,200-bed capacity tertiary government hospital in Davao City, Philippines. The DAC was founded in November 2000 by patients diagnosed with BA. The
club is supervised by residents of the Department of Family and Community Medicine, but it has its own set of officers, duly elected by the members
from among their fellow patients with BA. Club activities, including regular monthly meetings and consultations, lectures, and celebrations, are
geared towards education about BA, disease monitoring, efficient means of drug procurement, and social support. At present, the club has 57 registered
members. An average of 30 members are usually present during a meeting.
Male and female members of the DAC who were at least 18 years old and who had been with the club for at least six months were eligible to participate
in the study. We wanted for the study to detect a difference of PHP 1,000 in direct medical care costs between two comparison groups (i.e., controlled
asthma group versus uncontrolled asthma group) as statistically significant. Assuming a PHP 1,000 standard deviation of direct medical care costs and
an equal number of patients between two comparison groups, a total sample size of at least 34 patients will have 80% power of rejecting the null
hypothesis in a test for comparison of means carried at a <0.05 level of significance. We eventually recruited 35 patients into the study.
The primary outcome measures we were interested in were the level of asthma control among the participants of the study and asthma-related
direct medical care costs. We used two data collection tools for this study: a self-administered questionnaire and a structured diary.
The self-administered questionnaire was constructed in order to collect the demographic profile of patients, as well as their asthma control
scores. Upon enrolment into the study, we collected a patient's age, sex, civil status, occupation, and educational attainment. We also took the
baseline BA control score of a patient using the Filipino version of the Asthma
Control Test™ (ACT™).13
is a 5-question test designed for self-administration by 12-year-old or older patients with BA, in order to measure the degree to which their symptoms
are controlled for the past four weeks.14 15
This questionnaire, which includes an item about the patient's view of control, has been widely used, translated in many languages,
validated, and found to correlate well with doctors' rating of patients'
For each of the 5 items in the questionnaire, patients
would choose a score from 1 to 5, with 1 reflecting the worst and 5 reflecting the best control of asthma symptoms. The individual scores are then
added to come up with the total ACT™ score. A total score of 25 indicates totally controlled asthma, a score of 20-24 indicates partially controlled
asthma, while a score of 19 or lower indicates uncontrolled asthma. All the participants accomplished the self-administered questionnaires during
scheduled monthly meetings, and one of us (MAMF) was always present when the patients answered the questionnaires. We measured the ACT™ scores of
participants twice: at the end of their first month and at the end of their second month into the study. We considered participants to have controlled
asthma if their ACT™ scores were consistently between 20 and 25 within the two-month study. Participants who had at least one ACT™ score below 20
during the study were considered to have uncontrolled asthma.
We designed a structured diary, which was used by participants to record asthma-related expenses that they have incurred throughout the two-month
duration of the study. The participants classified each entry in the list of expenses into one of the following direct cost categories reflected in the
diary: diagnostics (e.g., cost of chest x-ray, spirometry, and arterial blood gases), asthma medications, outpatient consultation, emergency care
consultation, and hospital admission. For this study, only these direct costs of asthma-related medical care were considered. We did not account for
the indirect costs of asthma, such as the equivalent costs of lost wages and
during asthmatic exacerbation or recuperation from illness. We did not factor in other direct medical care costs of non-asthma diseases, such as those of
hypertension or diabetes comorbidities, in the list of expenses, either. We instructed the participants to reflect the actual costs of the products and
services in their diaries, even if they did not have to pay the entire or a portion of the costs (i.e., after discounts, fund assistance, etc.).
We also asked them to, whenever feasible, turn in a copy of the official receipt of payment for each item reflected in the diary. The corresponding
sources of funds for the items in the list of expenses were also indicated by the participants. Costs were covered by one or a combination of the
following fund sources: health insurance, out-of-pocket (from the patient's personal funds, or assistance from family or friends), external assistance
(from one or more of several medical assistance programs or social services available in the locality), and senior citizen discount.
We summarized categorical variables using frequencies and percentages. We summarized continuous variables using means and standard deviations,
and compared them using t-test. A two-sided alpha error of <0.05 was considered statistically significant. We did all statistical analyses in Epi Info
Data on demographic characteristics, asthma control and asthma-related medical care expenses were complete for all 35 patients who participated
in the study. Table 1 shows the demographic characteristics of the participants. The mean age of the participants was 56.86 ± 12.93 years. Majority
were females (25/35, 71.43% versus 10/35, 28.57% males). Most of the participants were married, (24/35, 68%), had no employment (25/35, 71.43%),
and had either high school (17/35, 48.57%) or college/vocational course education (14/35, 40%).
Demographic characteristics of patients with bronchial asthma
|Mean age ± SD, years
||56.86 ± 12.93
|Sex, frequency (%)
|Civil status, frequncy (%)
|Occupation, frequency (%)
|Educational attainment, frequncy (%)
| Elementary level
| High school level
| College or vocational course level
The direct costs of asthma-related medical care are summarized in Table 2. The average total direct medical cost was PHP 3,264.66 ± 3,076.39. Cost of
medications comprised the largest proportion (75.96%), while cost of diagnostics comprised the smallest proportion (1.51%) of the total direct medical cost.
Direct medical care cost of bronchial asthma in a 2-month period, according to cost category
||% of total
|†All values are in Philippine pesos (PHP).|
The sources of funds for asthma-related expenses are shown in Table 3. Most of the funds for medical care were sourced externally (65.28%). The mean
external assistance amount (PHP 2,131.14 ± 1,044.17) was more than twice the mean amount of out-of-pocket expenses (PHP 912.90 ± 2,770.16).
Direct medical care cost of bronchial asthma in a 2-month period, according to source of funds
|Source of funds
||% of total
|Senior citizen discount
|†All values are in Philippine pesos (PHP); *external assistance includes Lingap para sa Mahirap,
Congressional Medical Assistance Program (CMAP), and hospital social services.|
For the duration of the study, 24 (69%) participants had controlled asthma and 11 (31%) had uncontrolled asthma. Table 4 shows the comparative costs
of medical care between patients with controlled asthma and those with uncontrolled asthma. The total direct medical care costs of uncontrolled asthma
was more than twice as much as thatof controlled asthma (PHP 5,225.45 ± 4,885.37 versus PHP 2,365.96 ± 265.43, p=0.0085). Specifically, uncontrolled
asthma entailed significantly higher costs compared to controlled asthma in medications (PHP 3,189.27 ± 1,018.57 versus PHP 2,154.62 ± 728.01,
p=0.0016), outpatient consultations (PHP 140.91 ± 122.10 versus PHP 87.50 ± 22.12, p=0.0430), and hospital admissions (PHP 1,827.27 ± 4,364.42
versus PHP 0.00, p=0.0445). Among patients with controlled asthma, the cost of medications comprised 91.07% of the total direct medical care costs. Among those with
uncontrolled asthma, the cost of medications was only 61.03% of the total direct medical care costs, but the absolute average cost of the medications was
higher compared to that among patients with controlled asthma.
Direct medical care cost of bronchial asthma in a 2-month period, according to cost category and asthma control
||Controlled asthma (n=24)
||Uncontrolled asthma (n=11)
||% of total
||% of total
|†All values are in Philippine pesos (PHP); *statistically significant.|
In this two-month study among patients with asthma, we found out that cost of asthma medications constituted three-fourths of the total direct medical
care cost of the disease. Our findings also revealed that the total direct cost of medical care for uncontrolled asthma was more than twice the total direct
In this two-month study among patients with asthma, we found out that cost of asthma medications constituted three-fourths of the total direct medical care
cost of the disease. Our findings also revealed that the total direct cost of medical care for uncontrolled asthma was more than twice the total direct cost
of care for controlled asthma.
Strengths and limitations
We were able to successfully quantify the costs of medical care of asthma in our locality from the patients' perspective. This study was also able to
demonstrate the huge gap in costs of medical care between controlled and uncontrolled asthma, thereby highlighting the importance of symptom control in
the management of the disease.
Our study has several limitations. We did not include the indirect medical care costs of asthma, such as lost wages, and equivalent cost of lost
productivity during acute exacerbations and recuperation from asthma. If we considered indirect costs of asthma, the disparity in costs between controlled
and uncontrolled asthma or the comparative costs of the individual cost categories could possibly be different.8
In addition, our study focused only on patients' perspective about direct costs of medical care. Looking at the issue from the perspective of the government,
the hospital, or the health insurance companies could possibly generate different findings and insights. Finally, we measured BA control using the Asthma
Many other asthma-specific and patient-based measures are available with varying nature, validity, and ease of use, such as the Rule of
the 30-second test used in Canada,20
and the Royal College of Physicians Three Questions utilized in the United Kingdom.20
The use of other BA control tools could have produced different control classifications among our patients.
Medical care costs of asthma increase when the condition becomes poorly
When BA is uncontrolled, there is an increase in the need to seek emergency medical attention, and spend for diagnostics and therapeutics.
Asthma control is achieved by avoidance of factors that trigger symptoms and exacerbations and by maintaining prescribed medications. Improved
asthma control will reduce the number of asthma-related hospitalizations and can ultimately reduce direct health care costs.
Procurement of asthma medications is crucial to asthma control. In our study, asthma medication cost took up most of the total medical care costs
incurred by patients with asthma. It was lower in terms of percentage of total direct medical care costs among patients with uncontrolled asthma,
but the absolute cost was still higher compared to the asthma medication cost among patients with controlled asthma. Patients with uncontrolled asthma
spent relatively less for medications because they had to allot a third of their expenses to the cost of hospital admissions. Medications and hospitalization
for asthma-related causes are significant parts of health care expenditure, especially among
patients with uncontrolled asthma.6 8
Health care resources are burdened when the prevalence and
severity of asthma increase.4 5
Majority of the costs of illness comes from managing the effects of poorly controlled asthma. Hence, improving asthma control is clinically and economically
Patients with BA need adequate funds for their maintenance medications. Maintenance medications control asthma symptoms and prevent hospitalizations.
Health insurance can potentially protect patients with asthma from
At present, most health insurance benefit packages only cover the cost of hospital admissions related to asthma. This means that patients are only
protected from financial risk when their asthma symptoms become uncontrolled or when they develop complications of the disease. It also means that,
despite having health insurance, patients with asthma bear the financial burden of controlling their disease and keeping themselves from getting
hospitalized for asthma-related symptoms.
The results of our study can help patients and health care practitioners in making decisions around the medical care for patients with BA. The
results of this study can also guide health insurance policy makers in designing cost-efficient benefit packages for patients with BA. A benefit package
that includes not only coverage of hospitalization costs, but also coverage of maintenance medications, as well as outpatient diagnostic tests and
consultations intended to keep patients from experiencing symptoms of uncontrolled asthma, can help control asthma morbidity and potentially reduce
the overall costs of medical care for the disease.
Cost of medications comprised three-fourths of the direct medical care costs of asthma. Compared to patients with controlled asthma, those with
uncontrolled asthma spent more than twice for medical care.
We would like to express our sincerest appreciation to the Davao Asthma Club members whose unwavering participation made this study a success.
Our heartfelt gratitude also goes to the consultants and residents of the Department of Family and Community Medicine in Southern Philippines
Medical Center for their invaluable support and contributions to this study.
This study was reviewed and approved by the Department of Health XI Cluster Ethics Review Committee (DOHXI CERC reference 14082203).
Supported by personal funds of the author
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Copyright © 2015 Fabian MAM, et al.